LANGDON, Oliver Monroe, physician, born near Columbus, Ohio, 2 February, 1817; died there, 15 June, 1878. He studied at St. Xavier's college, Cincinnati, was graduated at the Medical college of Ohio in 1838, and after two years in Madison, Indiana, settled in Cincinnati. He was soon afterward appointed physician to one of the four townships into which the city was then divided, practised till 1846, then joined the 4th regiment of Ohio volunteers, and served as its surgeon till the close of the Mexican war. Dr. Langdon was one of the founders of Miami medical college, and an instigator of the movement that removed lunatics from the Cincinnati commercial hospital to the lunatic asylum at Lick Run, of which he was superintendent in 1850-'6. At that date he organized, and was made superintendent of, the insane asylum at Longview, continuing in office till 1870, when failure of health compelled his retirement from all active duties. Previous to 1866 all the colored insane in the state of Ohio had been confined in prisons at that date Dr. Lang-don established a separate department for their accommodation at Longview asylum, and, as the trustees of Longview could not, under their charter, own a negro institution, it was purchased in Dr. Langdon's name, and was held in trust for the county by him. He was a member of various medical societies, and a trustee of Miami medical college from its foundation till his death.